“The very progress we’ve made in HIV/AIDS over the last 20 years is at risk right now because of our lack of engagement with young women.” That was the stark message delivered by Ambassador Deborah Birx, the U.S. Global AIDS Coordinator, at a dynamic,

The data are stark and incontrovertible: In eastern and southern Africa, girls account for 80 percent of all new HIV infections among adolescents, and HIV/AIDS is the leading cause of death for girls aged 15–19. With 7,000 girls and young women aged 15–24...